There are a number of surgical procedures that relate to the treatment of intraluminal tissue, i.e., tissue located within a luminal structure such as the esophagus, colon, fallopian tube or urethra. Some of these procedures involve treating intraluminal tissue that is otherwise healthy, while others involve the treatment of diseased intraluminal tissue. For example, during a tubal sterilization procedure on a female patient, the intraluminal mucosal tissue of the fallopian tubes is defunctionalized by heating the tissue, thereby destroying it. In addition, one type of surgical treatment for stress incontinence involves heating the intraluminal tissue of the urethra, thereby shrinking or partially occluding the inner passage of the urethra so as to impede the passage of urine to a small, but necessary, degree. These are only a couple examples of the medical conditions and reasons that involve the controlled treatment of selected intraluminal tissue.
With reference to the treatment of diseased intraluminal tissue, there are various intraluminal disorders that occur in the tissues of luminal structures, including, but not limited to, the esophagus, jejunum, small intestine, fallopian tubes, colon and rectum. Left untreated, such diseases may progress into more serious, and potentially life-threatening, diseases. For example, in Barretts' esophagus the intraluminal mucosal lining has hyperplastic cells that, if left untreated, are at a very high risk over time of developing into malignant tissue, i.e., cancer.
Successful treatment of many such intraluminal disorders can be achieved by the application of heat to the diseased intraluminal tissue from within the luminal structure. However, application of heat radially to the entire circumference of the lumen may result in the unnecessary heating of healthy tissue and, in some cases, also causes stenosis of the luminal structure. Thus, it is preferable for the heat treatment to be applied selectively to the diseased intraluminal tissue or to treat the diseased intraluminal tissue in specified zones spaced over time.
Various methods of treating intraluminal disorders, achieving varying degrees of success, have been developed. For example, coagulation of the mucosal layer of Barretts' esophagus has been attempted using argon beam coagulation. This method of treatment has been less than optimal for the following reasons. First, the argon beam is difficult to initiate when the device is parallel to the esophagus wall. Second, the argon beam requires the surgeon to be relatively close to the esophagus wall. Lastly, the beam quickly quenches and thus leaves a small area of mucosal tissue treated, with untreated zones around it, which results in very spotty, discontiguous treatment of the diseased mucosal tissue.
In addition to the foregoing treatment method, other methods have used surgical ablation tools that require pressure against the mucosa and movement around the target region. Mucousectomy is another treatment method, which involves the surgical removal of the thin mucosal layer of the esophagus. A mucousectomy is difficult to perform because the instrumentation currently available in the GI endoscopy suite does not provide good access to the intraluminal area to be treated.
The device and method of the present invention address the shortcomings of the foregoing treatments for intraluminal tissues by providing for the selective heat treatment of a selected contiguous area of intraluminal tissue.